Method of manufacturing tipless miniature incandescent search-lamps.



PATENTED JULY 3, 1906.

0. A. BUHM. METHOD OF MANUFACTURING TIPLESS MINIATURE INGANDESCENTSEARCH LAMPS.

APPLIOATION FILED MAY 6, 1904.

UNITED STATES PATENT OFFICE.

OSCAR A. BGHM, OF NEW YORK, N. Y. METHOD OF MANUFACTURING TIPLESSMINIATURE INCANDESCENT SEARCH-LAMPS.

Specification of Letters Patent. A

' Patented Jul 3, 1906.

Application filed m 6. 1904. Serial No. 206,606.

To all whom it may concern:

Be it known that I, OSCAR A. BoHM, a citizen of the United States ofAmerica, and a resident of New York,county and State of New York, haveinvented certain new and useful Improvements in Methods of ManufacturingTipless Miniature Incandescent Search- Iiamps, of which the following isa specification.

This invention relates to a novel method of manufacturing tiplessminiature incandescent electric lamps, and pertains particularly to thattype of incandescent electric lamps purpose.

known as miniature search-lamps.

My lamp does not possess the usual tip at the top of the globe orvacuum-chamber, and therefore does not cast an undesirable shadow. Asthe name indicates ,miniature search-lamps are very small and whenprovided with a tip at the top of the globe, as informer constructions,the passage of light is obstructed. Owing to the small size of miniaturelamps, it is impossible to insert an exhaust-tube inside of the hollowstem, because there is no room for same, besides the stem is too shortfor this blow an exhaust-tube directlyto the lower portion or neck ofthe globe or vacuum-chamber. This will add prohibitive cost to' theprice of the lamp, because skilled labor is required for attaching anexhaust-tube to the lower part of the neck, owing to the small size ofsame and close proximity of the leading-in wires. Furthermore, lesslamps can be made per day Likewise the cost of producing such smalllamps with an exhaust-tube at the bottom end is so great as to render itimpossible to compete in the market. In the latter instance theleading-in wires must pass angularly through the side walls of the neck,which is undesirable for miniature lamps.

It is a special feature of my novel miniature search-lamp that the tipis neither at the top of the globe nor on or at the end of the neck. Notwithstanding," my lamp doesnot cost any more than the ordinaryminiature search-lamp, which latter has the exhausttip at the top of theglobe. This is due to the novel method of making same, and in additionhereto my lamp does not need to be tubulated, as will be describedfarther down. The application of such incandescent electric miniaturesearch-lamps is manifold.

They are preferably used'in connection with dry batteries, for instance,in the to portion of Walking-canes, \in the so-calle ever- Likewise itis impracticable toready flash-lights, as inspectors lamps, in

tories, and wherever explosive substances are 'manufactured. Further,they are used lamps are employed by plumbers in cellars, physicians atnight in the residences of patients, hunters, railroad trackmen,switchmen, operators, brakemen, oilmen, policemen, detectives,machinists, engineers, and

quired. large number are also used in electric novelties, such asscarf-pins, &c.

,The invention is illustrated in the accompanying drawings, in whichFigure lrepresents in side elevation the top portion of a miniaturesearch-light. Fig. 2 is a vertical section of same, showing the lamp inelevation. Fig. 3 represents a glass formed thereon. Fig. 4 illustratesthe glass tube having neck, contraction, and bulb formed thereon. Fig. 5shows the bulb and neck with wires and carbon sealed therein ready forexhaustion, and Fig. 6 shows the completed lamp sealed off.

parts in all the figures.

socket made of metal, in which the lamp b with base 0 is secured. Atubular holder (1 fits closely into the socketm. In the top portion ofsaid tubular holder d there is mounted a lens e. (See Figs. 1 and 2.) Itis plainly seen that the light emitted by the incandescent conductorwithin the lam must pass the lens e, while the li ht radiated on thesides of the incandescent amp will strike the metal walls of thelens-holder d. Therefore the lamp has no tip at the top of the globe orvacuum-chamber Z. tip min my novel miniature search-lamp is chamber, asshown in Figs. 2, 5, and 6. From Fig. 1 it is apparent that the lightemitted by through the lens free from any shadow.

In manufacturing iny lamp I substantially proceed as follows: A lasstube is drawn out to a point g, whic forms the handle.

shown in Fig. 3. So far there is practically no difference between thisand other lamps. Now the portion f of the glass tube is heated,

and whilejdoingthis thelfusing glass is turned coal-mines, asbicycle-lamps, in powder fac for all purposes Where a light is instantlyretube having a handle, neck, and contractionv Similar letters ofreferencev denote like i In the drawings, a. represents a tubular"located on one side of the globe or vacuum the lamp .is In no wayobstructed and passes Then a contraction h is formed thereon, as

on the guns of war vessels when adjusting the gun at night for firing.Likewise such On the contrary, the

in the flame and twisted in such a manner that the large quantity of thefused glass is on one side. Simultaneously the portion f of the tubewith the contraction is gradually moved sidewise. After the portion f ofthe glass tube has been heated in the described manner the bulb isblown, and while blowing same the portion f with the contractionh isfurther moved sidewise and upward until it is in the position indicatedin Fig. 4. The tube f constitutes now theeXhaust-tube. It must beobserved that according to the described method a lam bulb or globe isproduced which has no tip at the top of said globe or bulb. Still itpossesses the exhaust-tube away'from the top of the globe, although ithas not been: tubulated. When the bulb or globe is thus finished, theleading-in wires 'L i,

with su porting-braces j and carbon is, are" now sea ed into the globein the usual man- It is of course understood that" the wires,'withsupporting-brace and carbon, have been separately prepared. Now the lamis ready for exhaustion and may be applie "to the air-pump for thepurpose of creating a vacuum therein. After the vacuum' has been createdthe lamp is sealed in the usual manner and is now ready to receive thebase 0 and to be inserted in the socket a.

The method of manufacturing this lamp, and particularly the novel methodof blowing the bulb in such a manner that the v contraction hand theexhaust-tube f are in the position shown in Figs. l and, 5, insures aquick production of the lamp, and therefore the lamp will not cost anymore than the oldstyle lamp having the tip on the top. The

novel lamp, however, presents the advan tage of being 'a tipless lamp,for the urposes intended and does not share the de ciencies wise andupward so as to get the large quantity of glass on one side whereby aglobe is formed during one operation which has a smooth top and theexhaust-tube on theside.

with contraction is turned and twisted side- 2. The method of producingtipless incan- I descent miniature electric search-lam s consisting inblowing up the globe or bul while the exhaust-tube with contraction isturned and twistedsidewise and upward so as to get the large quantity oflass on one side whereby a globe is forme ,during one operation whichhas a smooth top and the exhaust on the side, inserting the wires withcarbon, ex-

hausting the lam and sealing it oif.

, Signed at New ork, N. Y. this 5th-day-of OSCAR A. BOHM.-

Witnesses:

Lunwre K. Roma, 3 JAMEs J. ASTARITA.

